I don’t mean this to sound patronising but I can’t get my head around living in another country for that length of time (with the exception of an Irish person in your particular situation) and not seeking citizenship at some point.
For the reasons I said although we did consider it early on way back, decades ago but couldn't afford it at the time. You're talking about changing nationality. Even though she loved the UK at the time, why would she want to become British and to apply for citizenship or what is now considered the right to stay didn't exist. And we didn't live in the Uk when all the sh!t happened.
PS She speaks perfect English, probably better than me. We are both bilingual.
My son-in-law is British and still only has British citizenship but applied for a residence permit (which is renewable), which he didn't need before, when Brexit happened and he's a proud Brit and doesn't want to change nationality.. My daughter has dual nationality like me but through birth. One of her children was born in the UK and also has dual nationality by birth. The youngest was born in France and only has French citizenship.
Crazy. Also it cost me €55 to take French Nationality. How much does it cost in the UK, a fortune.
Imagine the number of British people who were living in the EU or EU people living in the UK. It has affected so many lives in thousands of different ways other than what I've said above.
There are still a lot of Brits living without authority in the EU overstaying their 90 day visas. What is commonly known as illegal immigrants.